发明名称 |
Optical signal processing devices |
摘要 |
Optical signal processing devices, primarily intended for use in integrated optical communication systems, include 3 dB coupled strip guide directional couplers. Each coupler is formed in a body of electrooptic material and includes electrodes bracketing at least one of the guides in the coupled region. Each coupler is fabricated so as to be overcoupled (i.e., greater than 3 dB coupling) when the coupling is synchronous. Voltage bias, supplied to the electrodes of each coupler, produces sufficient asynchronism to independently adjust each coupler to the desired 3 dB coupling condition. Permutation switches are produced by including a switchable phase shifter between two couplers. Channel drop filters are produced by including reflection gratings between two couplers. Differential phase detectors, for a pulse code modulation system, are produced by including a selected path length difference between the two strip guides connecting two couplers. A photolithographic technique for producing the required electrodes in precise registry with the strip guide couplers (typically characterized by 3 micrometer spacings) includes the use of the primary strip guide mask and a secondary mask to produce a photolithographic mask for defining the electrodes.
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申请公布号 |
US4142775(A) |
申请公布日期 |
1979.03.06 |
申请号 |
US19760727047 |
申请日期 |
1976.09.27 |
申请人 |
BELL TELEPHONE LABORATORIES, INCORPORATED |
发明人 |
RAMASWAMY, VELLAYAN;STANDLEY, ROBERT D. |
分类号 |
G02F1/225;G02F1/313;(IPC1-7):G02B5/14 |
主分类号 |
G02F1/225 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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